Solar and wind energy outputs fluctuate between night and day and depending on the weather,, but robust energy storage solutions can smooth out the delivery of those clean energy sources to the power grid and ultimately help spur the addition of even more renewable energy to the grid.

The researchers tackled a long-standing problem with batteries, which is that the electrodes tend to degrade over several charge cycles and that causes them to lose capacity. That wearing down compromises the battery's ability store energy after a while and ultimately shortens its usable life. Obviously, when talking about large-scale batteries that will be connected to the power grid, you want the technology to be durable and long lasting.

In steps the Stanford team.

Gizmodo reports, "By coating the negatively charged cathode in copper hexacyanoferrate and using an anode made of activated carbon and a conductive polymer - compounds that allow electricity-carrying ions to move easily in and out - the team were able to build a prototype battery with electrodes that didn't lose capacity over time."

They made this enhancement to an aqueous electrolyte battery, a battery technology developed only eight years ago and the team says that all of the battery's components are cheap and commercially available.

"Virtually all of the energy-storage capacity currently on the grid is provided by pumped hydroelectric power, which requires an immense capital investment, is location-dependent and suffers from low energy efficiency," the team write.

Their development could provide a highly-efficient, long lasting solution.